Native Mercurial: fixed problems related to Git LFS
In-between GitLab v13.10.0-rc41 and v13.10.0, the LFS methods got systematically called, at least in HDK context. With the current HGitaly1 native repositories, this was calling Gitaly with a Mercurial changeset hash.
It is possible we won't even need these methods for future LFS integration on fully native (HGitaly2) repositories. We'll see when we get to that.